In general, an aerobic or anaerobic digestion treatment is performed in a completely stirred tank reactor (CSTR) that is being currently used.
However, strong organic wastewater introduced into a CSTR is completely mixed in the reactor and is discharged by the amount of introduced strong organic wastewater, in which case treatment efficiency and treatment rate are low.
In addition, an aerobic or anaerobic digestion treatment must be essentially accompanied by mixing of fluids in consideration of the properties and reactions of the fluids, therefore it is difficult to avoid complete mixing of fluids while performing a desired mixing operation.
Accordingly, a sequencing batch reactor (SBR) controlling mixing and discharge together, a separation reactor, or an upflow anaerobic sludge blanket (UASB) are being used in a treatment process, but they also show efficiencies similar to that of a CSTR.
Moreover, induction of treatment of strong organic wastewater by a CSTR is problematic due to recent global warming, generation of a large amount of strong wastewater, and regulation of total emission.